Combination treatment of cordycepin and radiation induces MA-10 mouse Leydig tumor cell death via ROS accumulation and DNA damage.

Leydig cell tumor is the most frequent non-germ cell tumors of testis. The biggest challenge of using radiotherapy to treat testicular cancer is in effectively killing cancer cells and maintaining reproductive function after treatment. Our recently published article showed that cordycepin could enhance radiosensitivity to induce mouse Leydig tumor cell apoptosis by inducing cell cycle arrest, caspase pathway and endoplasmic reticulum (ER) stress. In the present study, the potency and mechanism of a previous combination treatment protocol on reactive oxygen species (ROS) induction and DNA damage were further investigated. Our results reveal that 25 µM cordycepin plus 4 Gy radiation leads to ROS accumulation accompanied by a decrease in heme oxygenase (HO)-1 protein expression in MA-10 mouse Leydig tumor cells. Subsequently, pronounced DNA damage with phosphorylated H2A histone family member X (γ-H2AX) increase and activation of DNA damage-related signaling pathways including double and single stranded break-induced ataxia telangiectasia mutated (ATM)/checkpoint kinase (Chk)2 and ataxia telangiectasia mutated and Rad3 related (ATR)/Chk1 signaling axes were identified. p53-dependent pathway was then initiated ultimately leading to cell death. Preincubated with free radical scavenger, N-acetylcysteine (NAC), down-regulated γ-H2AX expression in treated cells and partially reduced cell death, indicating that ROS overproduction is involved in combination treatment-induced DNA damage. Furthermore, the combination treatment effectively inhibited tumor growth as reflected in the reduction of tumor volume, size and weight, and high expression level of γ-H2AX in tumor tissue in vivo, suggesting that the combination treatment inhibited tumor growth via causing DNA damage in MA-10 cells. In summary, these results expound that the combination treatment of cordycepin and radiation induces MA-10 mouse Leydig tumor cell death through ROS accumulation and DNA damage. This finding can serve as a reference guideline for future clinical therapy of testicular cancer and provide potential targets for anti-cancer drug design.

Effect of smile esthetics on the quality of life in a Han Chinese population.

OBJECTIVE: This study aimed to explore the influence of smile esthetics on the quality of life in a Han Chinese population. METHODS: A total of 110 Han Chinese volunteers (52 males and 58 females, mean age 26.7 years) were recruited, and frontal images of their smiles were collected. A photoediting program was used to evaluate the following components of smile esthetics: the buccal corridor ratios, the angle between the interpupillary and commissural lines, the number of visible teeth, and width-to-length ratios of the maxillary central incisors. Oral health-related quality of life (OHRQoL) in these volunteers was evaluated using the Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ) and Oral Health Impact Profile-14 (OHIP-14). Statistical analyses were performed by using Pearson's correlations and multiple linear regression (α = 0.05). RESULTS: Compared to males, females scored higher on psychological impact (p = 0.017). Moreover, the number of visible teeth had a significant effect on social impact, psychological impact and esthetic concern (all p < 0.05). However, the buccal corridor ratios, the angle between the interpupillary and commissural lines, and the width-to-length ratios of the maxillary central incisor did not correlate with the OHRQoL (all p > 0.05). CONCLUSIONS: The number of visible teeth significantly influenced the quality of life in a Han Chinese population. Smile esthetics had a significantly greater psychological impact on females than males. CLINICAL SIGNIFICANCE: This study highlights the effects of smile esthetics on the quality of life in a Han Chinese population. Female patients may raise more esthetic concerns in clinical practice.

Does laser treatment restore the bond strength of resin composites to recently bleached enamel? A systematic review and meta-analysis.

PURPOSE: To do a systematic review and meta-analysis to determine whether laser treatment affects the bond strength of resin composites to recently bleached enamel. METHODS: This report follows the Preferred Reporting Items for Systematic Reviews and Qualitative Analyses (PRISMA) statement. Medline via PubMed, Embase, Web of Science, and the Cochrane Library databases were searched with no limits on publication year. Two reviewers independently screened all titles and abstracts to perform the study selection, data extraction, and risk-of-bias assessments. A random-effects meta-analysis model was performed using Review Manager software (version 5.3, Cochrane Collaboration). RESULTS: From the 93 records identified, seven articles that met all the inclusion criteria were included in the systematic review, and six studies were included in the meta-analysis. The overall results showed a statistically significant difference in bond strength between the control group and laser-treated group (P= 0.04; mean difference: 5.27; 95% confidence interval: 0.28 to 10.27), favoring the laser-treated group. Subgroup analyses revealed that the tooth source (bovine or human teeth) contributed to the effect of laser treatment on the bleached enamel. CLINICAL SIGNIFICANCE: Laser treatment may increase the bond strength of resin composites to recently bleached enamel. Pretreatment with a laser, preferably with Nd:YAG (1 W, frequency of 10 Hz, irradiation time of 60 seconds) or CO2 lasers (0.5 W, frequency of 10 Hz, irradiation time of 60 seconds), may be recommended to restore the bond strength of recently bleached enamel.

Role of JNK activation in paclitaxel-induced apoptosis in human head and neck squamous cell carcinoma.

It has been reported that paclitaxel activates cell cycle arrest and increases caspase protein expression to induce apoptosis in head and neck squamous cell carcinoma (HNSCC) cell lines. However, the potential signaling pathway regulating this apoptotic phenomenon remains unclear. The present study used OEC-M1 cells to investigate the underlying molecular mechanism of paclitaxel-induced apoptosis. Following treatment with paclitaxel, cell viability was assessed via the MTT assay. Necrosis, apoptosis, cell cycle and mitochondrial membrane potential (∆Ψm) were analyzed via flow cytometric analyses, respectively. Western blot analysis was performed to detect the expression levels of proteins associated with the MAPK and caspase signaling pathways. The results demonstrated that low-dose paclitaxel (50 nM) induced apoptosis but not necrosis in HNSCC cells. In addition, paclitaxel activated the c-Jun N-terminal kinase (JNK), but not extracellular signal-regulated kinase or p38 mitogen-activated protein kinase. The paclitaxel-activated JNK contributed to paclitaxel-induced apoptosis, activation of caspase-3, -6, -7, -8 and -9, and reduction of ∆Ψm. In addition, caspase-8 and -9 inhibitors, respectively, significantly decreased paclitaxel-induced apoptosis. Notably, Bid was truncated following treatment with paclitaxel. Taken together, the results of the present study suggest that paclitaxel-activated JNK is required for caspase activation and loss of ∆Ψm, which results in apoptosis of HNSCC cells. These results may provide mechanistic basis for designing more effective paclitaxel-combining regimens to treat HNSCC.

Effects of remaining dentin thickness on the bond strength of bleached dentin.

BACKGROUND: The bond strength of resin composites to dentin was reported to be related to either the remaining dentin thickness (RDT) or bleaching treatment. However, information is limited regarding the effects of RDT on the bond strength of bleached dentin. The present study aimed to investigate the effects of RDT on the microshear bond strength (µSBS) of resin cement to bleached dentin. METHODS: A total of 120 dentin specimens were prepared and randomly divided into 2 groups: a bleaching group (group B) and a control group (group C). Hydrogen peroxide with a concentration of 35% (Ultradent, USA) was applied on the dentin surface for 2 × 1 d for group B, while no bleaching treatment was performed for group C. After the treatment, the specimens were finished and polished to obtain different RDTs (2, 1, and 0.5 mm) and divided into 3 groups of 20 specimens each. The bonding procedure was performed using Panavia V5 (Kuraray, Japan) with a bonding area of 0.785 mm2. For each group, half of the specimens were subjected to 5000 thermal cycles (subgroup T), while the other half did not receive thermocycling (subgroup N) (n = 10). The specimens were then subjected to the µSBS test using a universal testing machine. Data were analyzed by a three-way analysis of variance (α = 0.05). The fracture modes of the specimens were confirmed with a measuring microscope. Representative specimens with different fracture modes were observed with scanning electron microscopy (SEM). RESULTS: The µSBS values were significantly affected by bleaching treatment (p < 0.001), whereas no significant effect was observed for thermocycling (p = 0.293). In terms of RDT, a significantly different µSBS value was found among the subgroups with different RDTs in group C (p = 0.003). However, the RDT did not significantly affect the µSBS values of bleached dentin in group B (p = 0.779). The µSBS values were significantly lower in group B than in group C (p < 0.001). A higher percentage of adhesive failure was observed in group B than in group C. CONCLUSION: Based on the present findings, it can be concluded that the RDT did not affect the bond strength of resin cement to bleached dentin. CLINICAL SIGNIFICANCE: Since RDT did not affect the bond strength of resin cement to bleached dentin, bonding procedures should not be performed immediately after intracoronal bleaching, even if the dentin is planned to be removed due to a tooth preparation process.

De Novo synthesis of platinum-nanoparticle-encapsulated UiO-66-NH2 for photocatalytic thin film fabrication with enhanced performance of phenol degradation.

The structural and chemical stability of UiO-66-NH2 and its simulated solar irradiation responsive characteristic make it a suitable metal-organic framework (MOF) candidate as photocatalytic material. Platinum nanoparticles (Pt NPs) are typically immobilized in MOF to enhance the photocatalytic efficiency. However, introducing high metal content in MOF with high dispersion is still challenging using conventional methods. In this paper, we present de novo synthesis of Pt@UiO-66-NH2, which can reach a highest metal content of 16 wt% with an average nanoparticle size of around 2 nm as confirmed by ICP-MS analysis and TEM images. The presence of benzoic acid plays multiple important roles in Pt@UiO-66-NH2 formation, including binding formation with Zr clusters, facilitating Pt dispersion, and being a modulator in MOF construction. In addition, the Pt@UiO-66-NH2 is fabricated on the α-Al2O3 substrate as a photocatalytic membrane reactor (PMR) for phenol degradation, which shows over 70 % removal efficiency under light irradiation and H2O2 addition. The recycle test shows that the PMR can maintain high catalytic efficiency. The facile de novo synthesis method proposed in this study enables effective immobilization of high metal content in MOF, and construction of membrane-based photocatalyst for scale-up application.

Short-term effects of stain-causing beverages on tooth bleaching: A randomized controlled clinical trial.

OBJECTIVES: To evaluate the short-term effects of stain-causing beverages on the effectiveness of in-office tooth bleaching. METHODS: Participants were recruited and randomly divided into 3 groups based on beverages used for rinsing during and after the bleaching procedure: group N (tap water, control group), group C (coffee), and group T (tea). Participants were instructed to rinse with the respective solutions for 30 s, 4 times daily for 4 weeks. All participants received two in-office bleaching treatment sessions with 40 % hydrogen peroxide (Opalescence BOOST PF 40 %, Ultradent); the sessions were separated by a 1-week interval. Tooth colour was assessed using a spectrophotometer (Easyshade, Vita ZahnFabrik) before the bleaching procedure (T0), immediately after the first session of bleaching (T1), immediately after the second session of bleaching (T2), as well as one week (T3) and three weeks after (T4) the end of bleaching. Tooth sensitivity (TS) was ranked using a numerical rating scale (NRS) and a visual analogue scale (VAS) at different time points. RESULTS: No significant difference in the whiteness index (W), △E, △a* and △b* values among the 3 groups was observed at any time interval (P for all > 0.05). At T4, the △L* value in group C was significantly lower than that in groups T and N (P = 0.022 and P = 0.001, respectively), though no significant difference in △L* values was observed among the 3 groups at T1 (P = 0.402), T2 (P = 0.643) and T3 (P = 0.177). Additionally, no significant difference was found in the TS values among the 3 groups at any of the evaluation time points (P for all > 0.05). CONCLUSIONS: Exposure to coffee or tea during the bleaching treatment period did not affect the effectiveness of the treatment. However, exposure to coffee after the bleaching treatment did affect the effectiveness of the treatment. Exposure to stain-causing beverages did not affect the bleaching-induced TS (ClinicalTrials.gov Identifier: NCT03933527). CLINICAL SIGNIFICANCE: The consumption of coffee or tea during tooth bleaching may not interfere with the colour change produced by the treatment. However, clinicians should advise their patients to refrain from, at least to some extent, consuming coffee after the bleaching procedure to maintain the effectiveness of the treatment.

Comparison of smile esthetics among celebrities, dentists, and dental students in a Han Chinese population.

STATEMENT OF PROBLEM: Various components of smile esthetics have been evaluated. However, whether these components affect smile esthetics in Han Chinese celebrities, dentists, and dental students is unknown. PURPOSE: The purpose of this study was to evaluate the smile esthetics of celebrities, dentists, and dental students in a Han Chinese population. MATERIAL AND METHODS: Frontal images of smiles were obtained from the Internet for the celebrity group, while images of dentists and dental students were collected for the dentist and dental student groups. The buccal and posterior corridor ratios, the alignment discrepancy between the commissural and interpupillary lines, the number of teeth revealed, the width ratio relative to the golden proportion, and the width-to-length ratios of maxillary anterior teeth were calculated by using a photo-editing software program. Statistical analysis was performed by using 2-way ANOVA and the Tukey HSD test (α=.05). RESULTS: Eligible images were obtained for 81 celebrities, 83 dentists, and 78 dental students. The celebrities were found to have the highest buccal and posterior corridor ratios and reveal the least teeth in the smile among the 3 groups (all P<.001). The alignment discrepancy for celebrities was significantly less than that for dental students (P=.025). Moreover, the absolute difference of width ratios from the golden proportion was significantly different from 0 for all groups (all P<.001). CONCLUSIONS: Significant differences were found in the smiles of Han Chinese celebrities, dentists, and dental students in regard to the buccal and posterior corridor ratios, the alignment discrepancy between the commissural and interpupillary lines, and the number of teeth revealed. Chinese celebrities tended to have a smile that displays to the second premolar, with a medium buccal corridor width.

Arsenic compounds induce apoptosis through caspase pathway activation in MA-10 Leydig tumor cells.

The incidence of testicular cancer is increasing worldwide. Leydig cell tumors represent one type of sex cord-stromal testis malignancy, which tend to respond unfavorably to chemotherapies. Identifying more efficient treatment strategies is therefore crucial for patients. The present study aimed to investigate the apoptotic effects of arsenic compounds and their underlying mechanisms. The results indicated that sodium arsenite and dimethylarsenic acid induced apoptosis of the murine Leydig tumor cell line, MA-10. These apoptotic effects were characterized morphologically by membrane blebbing and cell detachment assays, biochemically using a cell viability assay, and cytologically by flow cytometry analysis. Western blotting demonstrated that caspases-3, -8 and -9, and poly(ADP-ribose) polymerase protein levels were increased compared with untreated MA-10 cells; however, the caspase inhibitor, Z-VAD-fmk, reversed these effects. In conclusion, the present study has shown that sodium arsenite and dimethylarsenic acid may activate the intrinsic and extrinsic caspase pathways, and induce MA-10 cell apoptosis. These results suggest that sodium arsenite and dimethylarsenic acid may represent novel approaches to treat clinically unmanageable forms of testicular cancer.

Finish-line designs for ceramic crowns: A systematic review and meta-analysis.

STATEMENT OF PROBLEM: Different finish-line designs have been advocated for tooth preparations of ceramic crowns. However, scientific evidence is lacking to help clinicians make a proper selection. PURPOSE: The purpose of this systematic review and meta-analysis was to evaluate the effects of finish-line designs on the marginal and internal adaptations of ceramic crowns. MATERIAL AND METHODS: This report follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The literature search was conducted in MEDLINE via the PubMed, Embase, and Web of Science databases with no publication year or language limits. In vitro studies comparing the marginal and internal adaptations of ceramic crowns with rounded shoulder and chamfer finish lines were included in the meta-analysis. RESULTS: Sixteen studies were included in the qualitative synthesis and meta-analyses. Statistical analyses were conducted using the Review Manager Software. Meta-analyses were performed with random-effects models (α=.05). Ceramic crowns with rounded shoulders exhibited significantly better marginal adaptation than those with chamfers (P<.001; mean difference=-7.8; 95% confidence interval=-11.6 to -4.1). Moreover, ceramic crowns with chamfers exhibited significantly better internal adaptation than those with rounded shoulders (P=.020; mean difference=35.0; 95% confidence interval=6.5 to 63.5). CONCLUSIONS: The difference in marginal adaptation of ceramic crowns using 2 finish-line designs was small, and the clinical significance was low, whereas the results of internal adaptation favored the chamfer finish line.

Medical Applications of Collagen and Hyaluronan in Regenerative Medicine.

In order to develop and commercialize for the regenerative medicinal products, smart biomaterials with biocompatibility must be needed. In this chapter, we introduce collagen and hyaluronic acid (HA) as extracellular matrix as well as deal with the molecular mechanism as microenvironment, mechanistic effects, and gene expression. Application of collagen and HA have been reviewed in the area of orthopedics, orthopedics, ophthalmology, dermatology and plastic surgery. Finally, the ongoing and commercial products of collagen and HA for regenerative medicine have been introduced.

Model-Based Orthodontic Assessments for Dental Panoramic Radiographs.

For better treatment outcomes, dentists usually use a set of parameters for orthodontic evaluation. In this study, a new method is proposed to assist dentists in obtaining reliable assessment of these parameters. The proposed method is based on dental panoramic radiographs and can be divided into four stages: image preprocessing, model training, tooth segmentation, and assessment of orthodontic parameters. The image is first normalized and enhanced. Then, the model training stage consists of shape and image model training, energy function training, and weight training. Next, we automatically segment the tooth contours in an energy-minimized manner. Finally, the automatic assessment of orthodontic parameters is carried out. The experimental results show that the average of absolute distance, the Dice similarity coefficient, and the average qualitative score ranged between 4.17 and 6.03, 0.87 and 0.90, as well as 2.58 and 3.12, respectively. The orthodontic assessment also is close to the evaluation of orthodontists. It has been shown that the proposed method can obtain accurate and consistent measurement in helping dentists to obtain an objective treatment evaluation.

Protecting-Group-Free Synthesis of 1-Phenylisoquinolin-4-ols: Thermal Cyclization of Methyl 2-[(Diphenylmethylidene)amino]acetates.

A protecting-group-free synthetic approach to 1-phenylisoquinolin-4-ols was developed by the intramolecular thermal cyclization of methyl 2-[(diphenylmethylidene)amino]acetates. R1 and R2 substituents were found to affect the required reaction temperatures, time, and yields of the cyclized products. The reactivity of the Schiff bases increased upon introduction of α-benzoyl and α-ester groups (R2). The cyclization yield also depended on the position of the R1 substituents on the phenyl groups.

Functional study of Cordyceps sinensis and cordycepin in male reproduction: A review.

Cordyceps sinensis has various biological and pharmacological functions, and it has been claimed as a tonic supplement for sexual and reproductive dysfunctions for a long time in oriental society. In this article, the in vitro and in vivo effects of C. sinensis and cordycepin on mouse Leydig cell steroidogenesis are briefly described, the stimulatory mechanisms are summarized, and the recent findings related to the alternative substances regulating male reproductive functions are also discussed.

Thymoquinone Attenuates Brain Injury via an Anti-oxidative Pathway in a Status Epilepticus Rat Model.

AIM: Status epilepticus (SE) results in the generation of reactive oxygen species (ROS), which contribute to seizure-induced brain injury. It is well known that oxidative stress plays a pivotal role in status epilepticus (SE). Thymoquinone (TQ) is a bioactive monomer extracted from black cumin (Nigella sativa) seed oil that has anti-inflammatory, anti-cancer, and antioxidant activity in various diseases. This study evaluated the protective effects of TQ on brain injury in a lithium-pilocarpine rat model of SE and investigated the underlying mechanism related to antioxidative pathway. METHODS: Electroencephalogram and Racine scale were used to value seizure severity. Passive-avoidance test was used to determine learning and memory function. Moreover, anti-oxidative activity of TQ was observed using Western blot and super oxide dismutase (SOD) activity assay. RESULTS: Latency to SE increased in the TQ-pretreated group compared with rats in the model group, while the total power was significantly lower. Seizure severity measured on the Racine scale was significantly lower in the TQ group compared with the model group. Results of behavioral experiments suggest that TQ may also have a protective effect on learning and memory function. Investigation of the protective mechanism of TQ showed that TQ-pretreatment significantly increased the expression of Nrf2, HO-1 proteins and SOD in the hippocampus. CONCLUSION: These findings showed that TQ attenuated brain injury induced by SE via an anti-oxidative pathway.

Facile manipulation of protein localization in fission yeast through binding of GFP-binding protein to GFP.

GFP-binding protein (or GBP) has been recently developed in various systems and organisms as an efficient tool to purify GFP-fusion proteins. Due to the high affinity between GBP and GFP or GFP variants, this GBP-based approach is also ideally suited to alter the localization of functional proteins in live cells. In order to facilitate the wide use of the GBP-targeting approach in the fission yeast Schizosaccharomyces pombe, we developed a set of pFA6a-, pJK148- and pUC119-based vectors containing GBP- or GBP-mCherry-coding sequences and variants of inducible nmt1 or constitutive adh1 promoters that result in different levels of expression. The GBP or GBP-mCherry fragments can serve as cassettes for N- or C-terminal genomic tagging of genes of interest. We illustrated the application of these vectors in the construction of yeast strains with Dma1 or Cdc7 tagged with GBP-mCherry and efficient targeting of Dma1- or Cdc7-GBP-mCherry to the spindle pole body by Sid4-GFP. This series of vectors should help to facilitate the application of the GBP-targeting approach in manipulating protein localization and the analysis of gene function in fission yeast, at the level of single genes, as well as at a systematic scale.

Differential Proteomic Analysis of Human Placenta-Derived Mesenchymal Stem Cells Cultured on Normal Tissue Culture Surface and Hyaluronan-Coated Surface.

Our previous results showed that hyaluronan (HA) preserved human placenta-derived mesenchymal stem cells (PDMSC) in a slow cell cycling mode similar to quiescence, the pristine state of stem cells in vivo, and HA was found to prevent murine adipose-derived mesenchymal stem cells from senescence. Here, stable isotope labeling by amino acid in cell culture (SILAC) proteomic profiling was used to evaluate the effects of HA on aging phenomenon in stem cells, comparing (1) old and young passage PDMSC cultured on normal tissue culture surface (TCS); (2) old passage on HA-coated surface (CHA) compared to TCS; (3) old and young passage on CHA. The results indicated that senescence-associated protein transgelin (TAGLN) was upregulated in old TCS. Protein CYR61, reportedly senescence-related, was downregulated in old CHA compared to old TCS. The SIRT1-interacting Nicotinamide phosphoribosyltransferase (NAMPT) increased by 2.23-fold in old CHA compared to old TCS, and is 0.48-fold lower in old TCS compared to young TCS. Results also indicated that components of endoplasmic reticulum associated degradation (ERAD) pathway were upregulated in old CHA compared to old TCS cells, potentially for overcoming stress to maintain cell function and suppress senescence. Our data points to pathways that may be targeted by HA to maintain stem cells youth.

Molecular mechanism of extrinsic factors affecting anti-aging of stem cells.

Scientific evidence suggests that stem cells possess the anti-aging ability to self-renew and maintain differentiation potentials, and quiescent state. The objective of this review is to discuss the micro-environment where stem cells reside in vivo, the secreted factors to which stem cells are exposed, the hypoxic environment, and intracellular factors including genome stability, mitochondria integrity, epigenetic regulators, calorie restrictions, nutrients, and vitamin D. Secreted tumor growth factor-ß and fibroblast growth factor-2 are reported to play a role in stem cell quiescence. Extracellular matrices may interact with caveolin-1, the lipid raft on cell membrane to regulate quiescence. N-cadherin, the adhesive protein on niche cells provides support for stem cells. The hypoxic micro-environment turns on hypoxia-inducible factor-1 to prevent mesenchymal stem cells aging through p16 and p21 down-regulation. Mitochondria express glucosephosphate isomerase to undergo glycolysis and prevent cellular aging. Epigenetic regulators such as p300, protein inhibitors of activated Stats and H19 help maintain stem cell quiescence. In addition, calorie restriction may lead to secretion of paracrines cyclic ADP-ribose by intestinal niche cells, which help maintain intestinal stem cells. In conclusion, it is crucial to understand the anti-aging phenomena of stem cells at the molecular level so that the key to solving the aging mystery may be unlocked.

An electrocatalytic oxidation and voltammetric method using a chemically reduced graphene oxide film for the determination of caffeic acid.

The present work describes the characterization of a chemically reduced graphene oxide (CRGO) modified glassy carbon electrode (GCE) for electrochemical investigation of caffeic acid (CA). Cyclic voltammetry (CV), differential pulse voltammetry (DPV), amperometry, and electrochemical impedance spectroscopy (EIS) techniques were used to characterize the properties of the electrode. There was an obvious enhancement of the current response and a decreased over potential for the oxidation of CA. The interfacial electron transfer rate of CA was studied by EIS. Under optimal conditions, the CRGO displayed a linear response range of 1×10(-8) to 8×10(-4) M and the detection limit was 2×10(-9) M (S/N=3), with a sensitivity of 192.21 µA mM(-1) cm(-2) at an applied potential of +0.2V (vs. Ag/AgCl reference), which suggests that the CRGO is a promising sensing materials for the electrochemical investigation of CA. The results showed the good sensitivity, selectivity and high reproducibility of the CRGO modified electrode. Moreover, this modified electrode was further applied to investigate the CA in real samples of wine with satisfactory results.

Apoptotic effect of cisplatin and cordycepin on OC3 human oral cancer cells.

OBJECTIVE: To evaluate apoptotic effects of cisplatin and cordycepin as single agent or in combination with cytotoxicity in oral cancer cells. METHODS: The influences of cisplatin (2.5 µg/mL) and/or cordycepin treatment (10 or 100 µmol/L) to human OC3 oral cancer cell line were investigated by morphological observation for cell death appearance, methylthiazoletetrazolium (MTT) assay for cell viability, flow cytometry assay for cell apoptosis, and Western blotting for apoptotic protein expressions. RESULTS: Data demonstrated that co-administration of cisplatin (2.5 µg/mL) and cordycepin (10 or 100 µmol/L) resulted in the enhancement of OC3 cell apoptosis compared to cisplatin or cordycepin alone treatment (24 h), respectively (P <0.05). In flow cytometry assay, percentage of cells arrested at subG1 phase with co-treatment of cordycepin and cisplatin (30%) was significantly higher than cisplatin (5%) or cordycepin (12%) alone group (P <0.05), confirming a synergistically apoptotic effect of cordycepin and cisplatin. In cellular mechanism study, co-treatment of cordycepin and cisplatin induced more stress-activated protein kinase/Jun terminal kinase (JNK), the expressions of caspase-7, and the cleavage of poly ADP-ribose polymerase (PARP) as compared to cisplatin or cordycepin alone treatment (P <0.05). CONCLUSION: Cisplatin and cordycepin possess synergistically apoptotic effect through the activation of JNK/caspase-7/PARP pathway in human OC3 oral cancer cell line.